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Screening Aid to Identify Corneas That May Have Pathologies or Other Conditions

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT00396188
Recruitment Status : Completed
First Posted : November 6, 2006
Last Update Posted : August 17, 2015
Sponsor:
Information provided by (Responsible Party):
Carl Zeiss Meditec, Inc.

Brief Summary:
The purpose of this study is to determine the ability of a proprietary software screening tool to discriminate normal corneas (front surface of the eye) from previously diagnosed corneal conditions (diseases/surgeries/pathologies) and to determine the repeatabiltity and reproducibility of the Atlas II corneal topographer in normal human corneas.

Condition or disease
Corneal Diseases

Detailed Description:
  1. To establish reference values for SF, CIM, and TKM in subjects with normal corneas.
  2. To establish reference values for SF, CIM, and TKM in subjects who underwent myopic laser vision correction.
  3. To establish reference values for SF, CIM, and TKM in subjects who underwent hyperopic laser vision correction.
  4. To establish reference values for SF, CIM, and TKM in subjects who were diagnosed to have keratoconus.
  5. To establish reference values for SF, CIM, and TKM in subjects with history of orthokeratology.
  6. To establish reference values for SF, CIM, and TKM in subjects with previously diagnosed corneal conditions (diseases/pathologies/surgeries) affecting the corneal surface that are not listed above.
  7. To determine the repeatabiltity and reproducibility of the Atlas II corneal topographer in normal human corneas using true elevation data and axial curvature.
  8. To determine the sensitivity, specificity, and accuracy of the Pathfinder II Corneal Analysis software in discriminating normal corneas from previously diagnosed corneal conditions (diseases/pathologies/surgeries) affecting the corneal surface (Phase II).

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Study Type : Observational
Actual Enrollment : 769 participants
Observational Model: Case Control
Time Perspective: Cross-Sectional
Official Title: Corneal Analysis - Pathology Detection Aid
Study Start Date : February 2007
Actual Primary Completion Date : February 2008
Actual Study Completion Date : February 2008

Resource links provided by the National Library of Medicine


Group/Cohort
Normals
  1. Patients seeking initial laser vision correction that were screened to be good candidates for the procedure.
  2. No history of refractive or other ocular surgery.
  3. No corneal pathologies.
  4. Normal corneal topography.
  5. Contact lens wearers should discontinue use at least 2 weeks for hard contacts, and 3 days for soft lenses prior to imaging.
Keratoconus
  1. An irregular cornea determined by distorted keratometry mires, distortion of the retinoscopic, or ophthalmoscopic red reflex (or a combination of these)
  2. At least one of the following biomicroscopic signs: Vogt's striae, Fleischer's ring of >2 mm arc, or corneal scarring consistent with keratoconus.
  3. Contact lens wearers should discontinue use preferably 1 day or at least half an hour prior to imaging.
Myopic Laser Vision Correction

Patients who have undergone myopic:

  1. LASIK
  2. PRK
  3. LASEK
Hyperopic Laser Vision Correction

Patients who have undergone hyperopic:

  1. LASIK
  2. PRK
  3. LASEK
Orthokeratology
1. Patients using specially designed rigid contact lenses to reshape the cornea to temporarily reduce or eliminate refractive error.
Others
1. Corneal conditions (diseases/ pathologies/surgeries) that can potentially affect the corneal surface that are not listed above (e.g. pellucid marginal degeneration; postoperative corneal transplant, intra-corneal ring segments, refractive keratotomy, conductive keratoplasty; peripheral ulcerative keratitis, Terrien's marginal degeneration; etc.).



Primary Outcome Measures :
  1. Reference values of normal and previously diagnosed corneal conditions by Atlas II corneal topographer [ Time Frame: 1-2 hours ]

Secondary Outcome Measures :
  1. Repeatabiltity and reproducibility of the Atlas II corneal topographer in human corneas [ Time Frame: 1-2 hours ]


Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
Subjects will consist of patients seeking consult in the Principal Investigator's (PI) clinical practice and volunteers responding to the study's advertisements.
Criteria

Inclusion Criteria:

Normals

  • Patients seeking initial laser vision correction that were screened to be good candidates for the procedure.
  • No history of refractive or other ocular surgery.
  • No corneal pathologies.
  • Normal corneal topography.
  • Contact lens wearers should discontinue use at least 2 weeks for hard contacts, and 3 days for soft lenses prior to imaging.

Keratoconus

  • An irregular cornea determined by distorted keratometry mires, distortion of the retinoscopic, or ophthalmoscopic red reflex (or a combination of these)
  • At least one of the following biomicroscopic signs: Vogt's striae, Fleischer's ring of >2 mm arc, or corneal scarring consistent with keratoconus.
  • Contact lens wearers should discontinue use preferably 1 day or at least half an hour prior to imaging.

Myopic Laser Vision Correction

Patients who have undergone myopic:

  • LASIK
  • PRK
  • LASEK

Hyperopic Laser Vision Correction

Patients who have undergone hyperopic:

  • LASIK
  • PRK
  • LASEK

Orthokeratology

  • Patients using specially designed rigid contact lenses to reshape the cornea to temporarily reduce or eliminate refractive error.
  • Subjects must be 18 years of age or older; able and willing to make the required visit; and able and willing to give consent.

Exclusion Criteria:

  • Patients that underwent corneal transplantation or any ocular surgery for the following categories: normal, keratoconus, and orthokeratology)
  • Any active infection or inflammation of the cornea.
  • PI decides that subject is not suitable due to medical risk.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00396188


Locations
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United States, California
Shiley Eye Center-University of California San Diego
La Jolla, California, United States, 92093
Carmel Mountain Vision Care Center
San Diego, California, United States, 92129
United States, Colorado
Dishler Laser Institute
Greenwood Village, Colorado, United States, 80111
United States, Oregon
Pacific University
Forest Grove, Oregon, United States, 97116
Sponsors and Collaborators
Carl Zeiss Meditec, Inc.
Investigators
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Principal Investigator: Jon Dishler, M. D. Dishler Laser Institute
Principal Investigator: David J Schanzlin, M. D. Shiley Eye Center-University of California San Diego
Principal Investigator: Dennis Burger, O. D. Kaiser Permanente, Oakland
Principal Investigator: Patrick Caroline, COT Pacific University
Principal Investigator: Tyson Brunstetter, O. D. Naval Training Center-Refractive Surgery Clinic
Principal Investigator: Kevin Reeder, O.D. Carmel Mountain Vision Care Center

Publications:
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Responsible Party: Carl Zeiss Meditec, Inc.
ClinicalTrials.gov Identifier: NCT00396188    
Other Study ID Numbers: Atlas II-2006-1-v1
First Posted: November 6, 2006    Key Record Dates
Last Update Posted: August 17, 2015
Last Verified: August 2015
Keywords provided by Carl Zeiss Meditec, Inc.:
Keratoconus
LASIK
Orthokeratology
Pellucid Marginal Degeneration
Refractive Surgery
normal cornea
post myopic LASIK
post hyperopic LASIK
corneal pathologies (e.g. pellucid marginal degeneration)
Additional relevant MeSH terms:
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Corneal Diseases
Eye Diseases